An electronic power device including transistors formed on a circuit assembly formed of a plurality of layers. The layers include gate drive layers, gate return layers, and power layers. A gate drive circuit is formed on the circuit assembly, and is connected to the gate and source of each of the transistors through the gate drive layers and the gate return layers. A voltage supply connection is provided to each of the plurality of transistors interleaved through the power layers. The circuit assembly includes a multilayer circuit board and/or a multilayer ceramic substrate. The ceramic substrate includes the power layers and transistors. The gate drive and return layers and gate drive circuit may be formed within the ceramic substrate or the circuit board. The ceramic substrate may be located in a modular housing. The circuit board may be outside the modular housing or inside the modular housing.